Additive manufacture of TiB<SUB align="right">2/Ti-6Al-4V metal matrix composite by selective laser melting

Abstract

In this study, a new material combination is evaluated for use with selective laser melting (SLM) methods of additive manufacturing. A 10 wt.% fine TiB2 powder was satellited onto the surface of a 90 wt.% Ti-6Al-4V powder to prevent segregations and promote homogeneity during processing. Solid structures of TiB2/Ti-6Al-4V were built using SLM Realiser 50 machine. Thereafter, the built structures were subjected to microstructural examination using optical and scanning electron microscopies. The hardness of the structure was determined using Vickers hardness tester. Results revealed that there was a reactive decomposition of the TiB2 powder which led to the formation of short (length ≤ 10 μm) and long (20-25 μm) TiB whiskers as reinforcements in the composites. The composite hardness was measured to vary from 440-503 HV0.3, signifying 30% increase when compared to Ti-6Al-4V hardness (350 HV0.3). Hence, processing satellited feedstock via SLM is promising for future product development.